Do On running shoes run true to size?
How On running shoes fit: length, width and which models to size up in.
The verdict
True to size, right across the range.
Yes: most On running shoes are true to size, with a standard width. Wide fits are available.
Mostly true to size. Reports vary more than for most brands, so if you can, try a pair first. A few everyday models come in a wide version.
- LengthTrue to size
- WidthStandard width
- Wide fitMen's: Wide · Women's: Wide
Your size in every On running shoe
Tell us your size in a On you already own, and we'll translate it across the range.
- Cloudboom MaxUK 9
- Cloudboom Strike 2UK 9
- Cloudflow 5UK 9
- Cloudmonster 3UK 9
- Cloudmonster 3 HyperUK 9
- Cloudrunner 3UK 9
- Cloudrunner 3 MaxUK 9
- CloudsomaUK 9
- Cloudsurfer 2UK 9
- Cloudsurfer MaxUK 9
- Cloudswift 4UK 9
- Cloudultra ProUK 9
- LightSpray Cloudmonster 3 HyperUK 9
A guide from how each model fits compared with the rest of the range. If you're between sizes, the brand's own size chart, measured against your foot, settles it.
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Between sizes?
Running shoes should leave about a thumb's width between your longest toe and the end of the shoe. Your feet swell on longer runs, so a shoe that feels just right in the shop can feel tight at mile ten. If you're between sizes, go up half a size for long runs and marathons; for short, fast race shoes, a closer fit is fine.
If your feet are wide, a wide version beats going up a size: a longer shoe adds length where you don't need it, and your foot can slide around.
Frequently asked questions
Should I size up in On running shoes?
Not usually: go with your normal size. If you're between sizes, or run long distances where your feet swell, half a size up gives your toes more room.
Do On make wide-fit running shoes?
Yes. The Cloudmonster 3, Cloudrunner 3, Cloudsurfer 2 and Cloudsurfer Max come in a wide fit.
Is On sizing the same as Nike's?
For length, mostly yes: your usual trainer size should work in both. Nike's race shoes are the exception, as they run small. Width is where they differ: On is a little roomier than most Nike running shoes.
How we know
We read what independent reviewers consistently report about each shoe's fit, alongside On's own guidance, and check which wide fits are actually on sale. As readers tell us how their shoes fit, we'll add that too.
Header photo by Jakub Balon